Adds IsNull() and IsNotNull() for all nullable types.

Author: tpierrain

NFluent.35.Tests/ObjectRelatedTest.cs

@@ -15,6 +15,8 @@
 
 namespace NFluent.Tests
 {
+    using NFluent.Tests.Extensions;
+
     using NUnit.Framework;
 
     [TestFixture]
@@ -41,11 +43,59 @@ public void IsDistinctWorks()
         }
 
         [Test]
-        public void IsNullWork()
+        public void IsNullWorks()
         {
             Check.That((object)null).IsNull();
         }
 
+        [Test]
+        public void IsNullWorksWithNullable()
+        {
+            Check.That((int?)null).IsNull();
+        }
+
+        [Test]
+        public void IsNotNullWorksWithNullable()
+        {
+            Mood? goodMood = new Mood();
+            Check.That(goodMood).IsNotNull();
+        }
+
+        [Test]
+        [ExpectedException(typeof(FluentCheckException), ExpectedMessage = "\nThe checked nullable value is null whereas it must not.")]
+        public void IsNotNullThrowsExceptionWithNullNullable()
+        {
+            Check.That((Mood?)null).IsNotNull();
+        }
+
+        [Test]
+        public void NotIsNullWorksWithNullable()
+        {
+            Mood? goodMood = new Mood();
+            Check.That(goodMood).Not.IsNull();
+        }
+
+        [Test]
+        public void NotIsNotNullWorksWithNullable()
+        {
+            Check.That((Mood?)null).Not.IsNotNull();
+        }
+        
+        [Test]
+        [ExpectedException(typeof(FluentCheckException), ExpectedMessage = "\nThe checked nullable value must be null.\nThe checked value:\n\t[NFluent.Tests.Extensions.Mood]")]
+        public void NotIsNotNullThrowsWithNonNullNullable()
+        {
+            Mood? goodMood = new Mood();
+            Check.That(goodMood).Not.IsNotNull();
+        }
+        
+        [Test]
+        [ExpectedException(typeof(FluentCheckException), ExpectedMessage = "\nThe checked nullable value is null whereas it must not.")]
+        public void NotIsNullThrowsExceptionWithNullNullable()
+        {
+            Check.That((Mood?)null).Not.IsNull();
+        }
+
         [Test]
         [ExpectedException(typeof(FluentCheckException), ExpectedMessage = "\nThe checked object must be null.\nThe checked object:\n\t[System.Object]")]
         public void IsNullFailsProperly()

NFluent.35/Assertions/ObjectCheckExtensions.cs

@@ -183,7 +183,7 @@ public static ICheckLink<ICheck<object>> InheritsFrom<T>(this ICheck<object> che
         /// </summary>
         /// <param name="check">The fluent check to be extended.</param>
         /// <returns>A check link.</returns>
-        /// <exception cref="FluentCheckException">Is the value is not null.</exception>
+        /// <exception cref="FluentCheckException">The checked value is not null.</exception>
         public static ICheckLink<ICheck<object>> IsNull(this ICheck<object> check)
         {
             var checker = ExtensibilityHelper.ExtractChecker(check);
@@ -199,6 +199,48 @@ public static ICheckLink<ICheck<object>> IsNull(this ICheck<object> check)
             return new CheckLink<ICheck<object>>(check);
         }
 
+        /// <summary>
+        /// Checks that the actual Nullable value is null.
+        /// </summary>
+        /// <param name="check">The fluent check to be extended.</param>
+        /// <returns>A check link.</returns>
+        /// <exception cref="FluentCheckException">The checked value is not null.</exception>
+        public static ICheckLink<ICheck<T?>> IsNull<T>(this ICheck<T?> check) where T : struct
+        {
+            var checker = ExtensibilityHelper.ExtractChecker(check);
+            return checker.ExecuteCheck(
+                () =>
+                {
+                    if (checker.Value != null)
+                    {
+                        var message = FluentMessage.BuildMessage("The checked nullable value must be null.").On(checker.Value).ToString();
+                        throw new FluentCheckException(message);
+                    }
+                }
+                , FluentMessage.BuildMessage("The checked nullable value is null whereas it must not.").ToString());
+        }
+
+        /// <summary>
+        /// Checks that the actual Nullable value is not null.
+        /// </summary>
+        /// <param name="check">The fluent check to be extended.</param>
+        /// <returns>A check link.</returns>
+        /// <exception cref="FluentCheckException">The checked value is null.</exception>
+        public static ICheckLink<ICheck<T?>> IsNotNull<T>(this ICheck<T?> check) where T : struct
+        {
+            var checker = ExtensibilityHelper.ExtractChecker(check);
+            return checker.ExecuteCheck(
+                () =>
+                {
+                    if (checker.Value == null)
+                    {
+                        var message = FluentMessage.BuildMessage("The checked nullable value is null whereas it must not.").ToString();
+                        throw new FluentCheckException(message);
+                    }
+                }
+                , FluentMessage.BuildMessage("The checked nullable value must be null.").On(checker.Value).ToString());
+        }
+
         /// <summary>
         /// Checks that the actual expression is not null.
         /// </summary>

ReleaseNoteContentToBeInsertedWithinNuspecFile.txt

@@ -1,4 +1,5 @@
 New feature(s):
+* Now supports IsNull() and IsNotNull() checks for nullables (thanks to Mendel Monteiro Beckerman for that).
 * Check.ThatCode(...): New entry point for checks on code (Action and Func<T>). It supersedes the equivalent Check.That signature.
 
 --------------
@@ -8,7 +9,7 @@ Change(s):
 * The HasFieldsEqualToThose() check is now obsolete and should be replaced by HasFieldsWithSameValues() which now support anonymous classes as expected parameter.
 * The HasFieldsNotEqualToThose() check is now obsolete and should be replaced by HasNotFieldsWithSameValues()
 * Simplification of extensibility
-* NFluent package is now signed
+* We are so proud of this 1.1 version of NFuent; we decided to sign it.
 
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 Bug Fixe(s):